﻿using System;
using System.ComponentModel;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Windows.Forms;

namespace Tools.Custom
{
    public class CustomPanel : System.Windows.Forms.Panel
    {
        #region 注释 老

        ///// <summary>
        ///// 建立圆角路径的样式。
        ///// </summary>
        //public enum RoundStyle
        //{
        //    /// <summary>
        //    /// 四个角都不是圆角。
        //    /// </summary>
        //    None = 0,
        //    /// <summary>
        //    /// 四个角都为圆角。
        //    /// </summary>
        //    All = 1,
        //    /// <summary>
        //    /// 左边两个角为圆角。
        //    /// </summary>
        //    Left = 2,
        //    /// <summary>
        //    /// 右边两个角为圆角。
        //    /// </summary>
        //    Right = 3,
        //    /// <summary>
        //    /// 上边两个角为圆角。
        //    /// </summary>
        //    Top = 4,
        //    /// <summary>
        //    /// 下边两个角为圆角。
        //    /// </summary>
        //    Bottom = 5,
        //}


        ///// <summary>
        ///// 建立带有圆角样式的路径。
        ///// </summary>
        ///// <param name="rect">用来建立路径的矩形。</param>
        ///// <param name="_radius">圆角的大小。</param>
        ///// <param name="style">圆角的样式。</param>
        ///// <param name="correction">是否把矩形长宽减 1,以便画出边框。</param>
        ///// <returns>建立的路径。</returns>
        //GraphicsPath CreatePath(Rectangle rect, int radius, RoundStyle style, bool correction)
        //{
        //    GraphicsPath path = new GraphicsPath();
        //    int radiusCorrection = correction ? 1 : 0;
        //    switch (style)
        //    {
        //        case RoundStyle.None:
        //            path.AddRectangle(rect);
        //            break;
        //        case RoundStyle.All:
        //            path.AddArc(rect.X, rect.Y, radius, radius, 180, 90);
        //            path.AddArc(rect.Right - radius - radiusCorrection, rect.Y, radius, radius, 270, 90);
        //            path.AddArc(rect.Right - radius - radiusCorrection, rect.Bottom - radius - radiusCorrection, radius, radius, 0, 90);
        //            path.AddArc(rect.X, rect.Bottom - radius - radiusCorrection, radius, radius, 90, 90);
        //            break;
        //        case RoundStyle.Left:
        //            path.AddArc(rect.X, rect.Y, radius, radius, 180, 90);
        //            path.AddLine(rect.Right - radiusCorrection, rect.Y, rect.Right - radiusCorrection, rect.Bottom - radiusCorrection);
        //            path.AddArc(rect.X, rect.Bottom - radius - radiusCorrection, radius, radius, 90, 90);
        //            break;
        //        case RoundStyle.Right:
        //            path.AddArc(rect.Right - radius - radiusCorrection, rect.Y, radius, radius, 270, 90);
        //            path.AddArc(rect.Right - radius - radiusCorrection, rect.Bottom - radius - radiusCorrection, radius, radius, 0, 90);
        //            path.AddLine(rect.X, rect.Bottom - radiusCorrection, rect.X, rect.Y);
        //            break;
        //        case RoundStyle.Top:
        //            path.AddArc(rect.X, rect.Y, radius, radius, 180, 90);
        //            path.AddArc(rect.Right - radius - radiusCorrection, rect.Y, radius, radius, 270, 90);
        //            path.AddLine(rect.Right - radiusCorrection, rect.Bottom - radiusCorrection, rect.X, rect.Bottom - radiusCorrection);
        //            break;
        //        case RoundStyle.Bottom:
        //            path.AddArc(rect.Right - radius - radiusCorrection, rect.Bottom - radius - radiusCorrection, radius, radius, 0, 90);
        //            path.AddArc(rect.X, rect.Bottom - radius - radiusCorrection, radius, radius, 90, 90);
        //            path.AddLine(rect.X, rect.Y, rect.Right - radiusCorrection, rect.Y);
        //            break;
        //    }
        //    path.CloseFigure(); //这句很关键，缺少会没有左边线。
        //    return path;
        //} 
        #endregion

        #region 属性

        /// <summary>
        /// 控件边框颜色
        /// </summary>
        [Category("自定义"), Description("控件边框颜色")]
        public Color BorderColor
        {
            get; set;
        }

        /// <summary>
        /// 圆角大小 默认值10
        /// </summary>
        [Category("自定义"), Description("圆角大小 默认值0 直角")]
        public int RoundAngle
        {
            get; set;
        }

        /// <summary>
        /// 填充背景色
        /// </summary>
        [Category("自定义"), DefaultValue(typeof(Color), "#DDDDDD"), Description("填充背景色")]
        public Color FillBackColor { get; set; }

        ///// <summary>
        ///// 默认圆角边框
        ///// </summary>
        //[Category("自定义"), DefaultValue(typeof(RoundStyle), "0"), Description("默认圆角边框")]
        //public RoundStyle RoundeStyle { get; set; }

        #endregion

        #region 绘制填充色

        protected override void OnPaint(PaintEventArgs e)
        {
            if (this.RoundAngle > 0)
            {
                int width = base.Width - base.Margin.Left - base.Margin.Right;
                int height = base.Height - base.Margin.Top - base.Margin.Bottom;
                Rectangle rec = new Rectangle(base.Margin.Left, base.Margin.Top, width, height);
                GraphicsPath round = CreateRound(rec, this.RoundAngle);
                e.Graphics.SmoothingMode = SmoothingMode.AntiAlias;
                e.Graphics.FillPath((Brush)(new SolidBrush(this.FillBackColor)), round);
            }
        }

        protected GraphicsPath CreateRound(Rectangle rect, int radius)
        {
            GraphicsPath roundRect = new GraphicsPath();
            //顶端 
            roundRect.AddLine(rect.Left + radius - 1, rect.Top - 1, rect.Right - radius, rect.Top - 1);
            //右上角 
            roundRect.AddArc(rect.Right - radius, rect.Top - 1, radius, radius, 270, 90);
            //右边 
            roundRect.AddLine(rect.Right, rect.Top + radius, rect.Right, rect.Bottom - radius);
            //右下角

            roundRect.AddArc(rect.Right - radius, rect.Bottom - radius, radius, radius, 0, 90);
            //底边 
            roundRect.AddLine(rect.Right - radius, rect.Bottom, rect.Left + radius, rect.Bottom);
            //左下角 
            roundRect.AddArc(rect.Left - 1, rect.Bottom - radius, radius, radius, 90, 90);
            //左边 
            roundRect.AddLine(rect.Left - 1, rect.Top + radius, rect.Left - 1, rect.Bottom - radius);
            //左上角 
            roundRect.AddArc(rect.Left - 1, rect.Top - 1, radius, radius, 180, 90);
            return roundRect;
        }
        #endregion
        
        #region 重绘圆角边框

        /// <summary>
        /// 建立带有圆角样式的路径。
        /// </summary>
        /// <param name="rect">用来建立路径的矩形。</param>
        /// <param name="_radius">圆角的大小。</param>
        /// <param name="style">圆角的样式。</param>
        /// <param name="correction">是否把矩形长宽减 1,以便画出边框。</param>
        /// <returns>建立的路径。</returns>
        GraphicsPath CreatePath(Rectangle rect, int radius, bool correction)
        {
            GraphicsPath path = new GraphicsPath();
            int radiusCorrection = correction ? 1 : 0;

            path.AddArc(rect.X, rect.Y, radius, radius, 180, 90);
            path.AddArc(rect.Right - radius - radiusCorrection, rect.Y, radius, radius, 270, 90);
            path.AddArc(rect.Right - radius - radiusCorrection, rect.Bottom - radius - radiusCorrection, radius, radius, 0, 90);
            path.AddArc(rect.X, rect.Bottom - radius - radiusCorrection, radius, radius, 90, 90);

            path.CloseFigure(); //这句很关键，缺少会没有左边线。
            return path;
        }


        protected override void WndProc(ref Message m)
        {
            try
            {
                base.WndProc(ref m);
                if (m.Msg == 0xF)
                {
                    if (this.RoundAngle > 0)
                    {
                        using (Graphics g = Graphics.FromHwnd(this.Handle))
                        {
                            Rectangle r = new Rectangle();
                            r.Width = this.Width;
                            r.Height = this.Height;
                            DrawBorder(g, r, this.RoundAngle);
                        }
                    }
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }

        private void DrawBorder(Graphics g, Rectangle rect, int radius)
        {
            rect.Width -= 1;
            rect.Height -= 1;
            using (GraphicsPath path = CreatePath(rect, radius, false))
            {
                using (Pen pen = new Pen(this.BorderColor))
                {
                    g.DrawPath(pen, path);
                }
            }
        } 
        #endregion
    }
}
